Shibou Yuugi de Meshi o Kuu.

At just seventeen, Yuki is a professional death game player. She’s survived enough rounds to know that survival is calculation, not luck—and that failure is final. For most players, the games are a nightmare with no escape. For Yuki, they’re simply business. Yet in a world where rooms turn into graves and every choice could be her last, even experience offers no protection.